Troubleshooting Adhesive Failure in Laminate over Luaun

QuestionI recently installed a laminate countertop. The laminate is beginning to separate from the substrate. The counter is 21' long. It is a Wilsonart post-form laminate over a luan substrate. There is one seam in the laminate. I used Sta-Put spray adhesive. The substrate was made on site and is one piece. I have done several fabrications but this is the first time that I have ever used a post-form laminate for the countertop and the first time that I have ever experienced separation of this kind. Any idea what could be causing this?

Forum Responses(Laminate and Solid Surface Forum)
From contributor P:If I recall correctly, Sta-Put has a short open time. On a top that big, I suspect you rolled the laminate after the open time. I would just use a heat gun and reactivate the glue and press it down. You can get it to roll down better with a steel roller.

From contributor J:Isn't luan that el cheapo porous Philippian mohagany? I've even seen that stuff a little damp. Maybe that is your problem.
From contributor G:Are you sure it's the laminate from the substrate or the top layer of the plywood separating from itself from the addition of the chemical from the Sta-put?
From contributor R:Where is the laminate pulling away from? The postform edge? The top of the deck? At the seam? What kind of postform edge is used? And which StaPut adhesive did you use?

SPH is a pressure sensitive adhesive. There is no way you went over the open time because it is unlimited. The longer you wait, the more pressure is needed to have the contact have a good bond. If you did not have at least 30psi (use a j roller or pinch roller) with this product, you probably achieved very superficial bonds. When your core and your laminate move (grow and shrink) at different rates, the bonds can be broken. This would cause bubbling. Also, if the pressure or adhesive coverage was not consistent, then this can cause bubbling too.

I work for Wilsonart Adhesives and Sta Put is a competitor of mine. But I never hear issues about failures with SPH unless someone waited too long and didn't put enough pressure on. Unless you are using a canister product. Now that's a whole list of other issues that I would be glad to help you out with. If it was a canister.

From contributor P:I respectfully disagree. The glues here in California (AQMD compliant) are similar and the open time is short. To say otherwise is giving a bum steer that will cause some trouble for anyone who follows your advice.
From contributor R:I am going to have to eat crow here. I thought StaPut SPH was a true pressure sensitive adhesive. I did more research after your last post. The StaPut web site says "complete bond within 60 minutes." It also states SPH has "some pressure sensitive properties." I apologize for saying it had an unlimited open time like a true pressure sensitive adhesive.
From contributor M:I would like to hear the negatives about the canister products. That's pretty much all I use and I've never had any problems, at least not for the three years I've been using it. I've heard the temp drop from the propellant causes moisture condensation that will cause problems, but even where I'm at in the humid south, it has never been an issue.
From contributor P:For me it is just cost.
From contributor R:When you get to the end of some canisters, they spit and sputter. Some canisters you can't get all of the adhesive out. Some canisters contain a wicked cancer causing solvent called Methylene Chloride. Some canisters state theirs does not contain Methylene Chloride but then it contains Dichloryl Methylene (spelling may be off). It's the same chemical - check the CAS#. Some canisters WEB so badly that they telegraph and make a huge mess in the shop. Always read the label. Get all guaranteed coverage rates in writing. There are some wonderful canisters and some that are so-so.
From contributor G:We're new to the canister adhesives. What are the wonderful ones? Where does Helmiprene 1685 (boss just got it in) stand? I still haven't received any instruction on the use, open time, etc.

One other question. In the past we used Wilsonart 950 and if we needed to peel it off, used solvent, let it dry, resprayed, restuck. Haven't had to do it yet with the canister, but can we - what solvent, etc.?

From contributor R:I have never used a canister made by Helmitin. I know Helmitin does make many good adhesives. Specifics on the open time you would have to get from their sales force. I wish I had better and more specific answers. You asked about the negatives of canister. I can answer that. But specifics about other folks' products I am staying away from. I will answer in depth anything about Wilsonart Adhesives.
From contributor G:We have used Formica clear 151 and red 150 for years and it always works great. They do make a spray can that also works great for onsite laminating. Can make one coat on the substrate and one on the laminate and within a minute or less it's ready to stick.
From contributor R:Hybond used to make Formica's adhesive. Henkel bought Hybond and then recently stopped making it and sold their formulas to a new adhesive company. I would love to know who is going to make Formica adhesive now.
From contributor D:It has nothing to do with post forming laminate. It is the glue or the substrate or temperature change. Did you bring the laminate in and lay it up on site that day? Was there climate control at the time? That is why I make my tops in the shop and then install them - always a better product.

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